Mastery learning is “both a philosophy of instruction and a set of methods for teaching and assessing” (Gentile & Lalley, 2003, p. 172). As a philosophy, it endorses the belief that, except for the most severely cognitively impaired, all children can learn what the schools are accountable for teaching. As a set of teaching and testing methods, it requires that each student be assessed in a criterion-referenced manner—that is, without reference to the performance of others—on how well he or she is achieving the required instructional objectives.

The belief that all children can learn was a central tenet of Benjamin Bloom's initial formulation of mastery learning in 1968. He deduced this from John Carroll's 1963 model of school learning, in which Carroll rejected the traditional norm-referenced ...